Disazo dyestuffs



Patented Aug. 30, 1938 UNITED STATES PATENT OFFICE DISAZO DYESTUFFS Jose Stephen Petrus-Blumberger, Delft, Netherlands, assignor to General Aniline Works, Inc., New York, N. Y., a corporation of Delaware No Drawing. Application April 22, 1936, Serial 'No. 75,884. In Germany May 2, 1935 v4 Claims wherein B stands for a radical of the benzene series'bearing the azo-group in'meta-position to the NH group, such as a benzene nucleus which.

may bear substituents, e. g. methyl, a halogen atom, or a carboxylic acid-group. .7 7;.

R stands for the radical of 1-amino-5-naphthol-7-sulfonic acid or of 2-amino-8-naphthol-6- sulfonic acid and R1 stands for a radical of 1- amino-5-naphthol-7-sulfonic "acid, 2-amino-8- naphthol-G-sulfonic acid, or 2-amino-5-naphthol-7-sulfonic acid, the 2 coupling components being coupled to the hydroxy side. I 25 My new dyestuffs are obtainable by coupling tetrazotized 3,3-diaminodiphenyl urea or a homologue thereof first with 1-amino-5-naphthol-7- sulfonic acid or 2-amino-8-naphth01-6-sulfonic acid and then with one of the said components 0 or 2-amino-5-naphthol-7-sulfonic acid.

The dyestufis thus obtainable can be tetrazotized on the fiber and developed with the usual developers such as B-naphthol or toluylene diamine.

In this manner are obtained in general Bordeaux to brown shades of good fastness to washing and good dischargeability, both, with a neutral and with an alkaline discharge paste.

The invention is illustrated by the following 40 examples, but it is not restricted thereto.

Examples then the finished tetrazo solution is poured into a solution alkaline with sodium carbonate of 50 239 parts of 1-amino-5-naphthol-7-sulfonic acid.

The dyestufi, having in the free state the following formula:

' v HOzS is filtered ofi in the cold, squeezed and dried. It yields on cotton Bordeaux shades, which, after tetrazotizing and developing with fi-naphthol remain Bordeaux, with toluylene-diamine yield a reddish brown.

In an analogous manner have been prepared the dyestuffs of the following formula:

Both dyestuffs yield on cotton corinth shades, which, when tetrazotized and developed with toluylene-diamine, are turned to deep brown. When using B-naphthol as developer, the shade of the first dyestuff remains unchanged while that of the second dyestufi is turned to a bluish corinth.

I claim: 1. A20 dyestuffs of the general formula:

NHBN=N-R o I IH-BN=NR1 wherein B stands for a radical of the benzene series bearing the azo-group in meta-position to the NH group, R stands for the radical of an amino naphthol sulfonic acid of the group cohsisting of l-amino-5-naphthol-'7sulfonic acid and of 2-amino-8-naphtholfi-sulfonic acid and R1 stands for a radical of an amino naphthol sulfonic acid of the group consisting of 1-amino-5-naphthol-7-sulfonic acid, Z-amino-8-naphtho1-6-sulfonic acid, and 2-amino-5-naphthol-'7sulfonic HOaS yielding on cotton Bordeaux shades, which, after tetrazotizing and developing with e-naphthol remain Bordeaux, with toluylene-diamine yield a reddish brown.

3. The dyestuff having in its free state the following formula:

N=N I G 1103s ::\NH2

Q OH

N=N NH:

HOsS

yielding on cotton corinth shades, which, after tetrazotizing and developing with toluylenediamine are turned to deep brown.

4. The dyestuff having in its free state the following formula:

yielding on cotton corinth shades, which, after tetrazotizing and developing with toluylenediamine are turned to deep brown.

JOSE STEPHEN PETRUS-BLUMBERGER. 

